Water gurgling right at drain new sink

Just put in new vanity and vessel sink. Contractor had to reconfigure piping under sink with PVC. Sink came with pop-up stopper and tail piece. Loud water noise right below sink hole of water running through and some as it runs down PVC pipe to p trap. How do I fix it? It's loud and annoying but appears to be related to materials not any venting problems. Not a burgling, bubbling gurgle just trickling sounds.

Just put in new vanity and vessel sink. Contractor had to reconfigure piping under sink with PVC. Sink came with pop-up stopper and tail piece. Loud water noise right below sink hole of water running through and some as it runs down PVC pipe to p trap. How do I fix it? It's loud and annoying but appears to be related to materials not any venting problems. Not a burgling, bubbling gurgle just trickling sounds.

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I also installed a vessel sink with a pop up stopper. The sink has no overflow hole, which a normal lav sink has, and water going down the drain pulls air down with it, air maybe that a normal sink with overflow would aid the water going down the tail piece quietly. My DIY 2 cents homeowners opinion. the noise never bothered me though, but it does exist. think of it as sounds of tranquility

Thanks everyone for your comments. If you see another thread on this, sorry. I couldn't find my original thread. My husband thinks the noise is loud because the contractor immediately stepped up the pipe size to 2" PVC. My husband thinks the piece under the tailpiece should be the same size and metal and go a little ways and then step up to the bigger pipe size. That's what the other sinks in my house have if they have to run a long ways down to mee the p trap. What do you all think?

Not likely, but since we cannot hear the gurgling, (and "gurgling" can mean many things and have many causes), or see HOW he configured the drain line, (it is NOT likely to be 2" however), we cannot diagnose, or even comment, on it.